This is a nice example of complementary etymology. In Homer the word applies to living beings only; after Homer, it became a poetic word which can occasionally be used also for dead bodies (Sophocles). Scholiasts distinguished consequently two contextual meanings for which they give two different etymologies. The first one, linking demas with deō "to bind", is often found in scholiastic and philosophical literature. The "invention" of the etymological link with damazō "to tame", which has the same initial consonant sequence [d-m], is the logical consequence of the etymological link with deō "to bind": if demas is what binds the soul, this can no longer be the case after death, when the soul leaves the body and is no longer bound by anything. Therefore the word had to be motivated differently: in that case the etymology relies on the frequent use of the passive ἐδμήθη "he was tamed" with the meaning "he was killed" in Homer. The idea that one and the same word can have two different etymologies was not a problem for Greek philosophy, and each etymon was assigned to a specific context of use of the considered word. The etymologies are not competing, but complementary, each accounting for one context